Whale-Marking in the Southern Ocean

Abstract

IN 1925 the R.R.S. Discovery, Captain Scott's famous old ship, sailed once more for the south, and marked the beginning of the Discovery Committee's programme of Antarctic research which, as is well known, has been continued to the present time by the notable voyages of the R.R.S. Discovery II and the smaller R.R.S. William Scoresby. The investigations, carried out by a staff of oceanographers directed first by Dr. Stanley Kemp, f.r.s., and latterly by Dr. N. A. Mackintosh, have been made by the Committee under the instructions of the Secretary of State for the Colonies. They were planned on broad lines to inquire into the resources of the Antarctic seas and their possible development, and one of their primary objects is the scientific regulation of the great whale fisheries of these waters. Their scope is as wide as the southern ocean, embracing a study of all the factors, biological and physical, that may influence directly or indirectly the lives of these huge mammals. General accounts of these voyages have been given to the Royal Geographical Society by members of the staff from time to time x and the scientific results, still being published, have already filled nineteen large volumes of the Discovery Reports. One of the most recently published reports is that by Mr. George Rayner, entitled 'Whale marking: progress and results to December 1939.' * Much has been learnt about the lives of fish by marking experiments. The fish are caught, measured, and then set free labelled with a little button which bears a number and a mark signifying the country of origin: rewards are paid to fishermen who return such numbered fish with details of the place and date of recapture. Many thousands of fish have been so marked and liberated in the North Sea by the fishery naturalists of different nations and many hundreds have been returned. In this way the principal migrations of a number of species have been charted and information gained as to their rates of growth in different localities and during various intervals of time. These experiments have further provided valuable indications of the intensity of fishing of different stocks of fish; more than 40 per cent. of marked plaice have been recaptured in a single